Whether you went to work or just went to the bathroom, your baby now understands that his favorite person in the world sometimes leaves. And he’s not too thrilled about it.

According to Tovah Klein, PhD, director of the Barnard College Center for Toddler Development and author of “How Toddlers Thrive,” many babies at this stage begin to show signs of separation anxiety and stranger anxiety.

Dr. Klein explains how baby is more aware of unfamiliar people and places and may cry when someone new holds them (even if they’re usually a social butterfly), and recommends giving your baby extra time to warm up to new situations.

If you’re going to leave them with a family member, friend or caregiver, be sure to stick around for a bit to ease them into the adjustment process. When they feel comfortable, they’ll act more like themselves and start to play.

Related: 8-month-old baby milestones

Sensory activities for 8-month-olds

1. Number games

Infants as young as 9 months can perform numerical computations with numbers up to 10, even before they can verbalize these skills, studies show. Start prepping for this concept by introducing addition and subtraction into your daily routine. Add finger foods to baby’s tray one by one, count down from 10 as you blast off their rocket ship toy and sing counting songs together.

2. Make a baby-safe kitchen basket

Exploring by tasting literally everything they come across is just one of the ways 8-month-old babies gain sensory input. Make a baby-safe kitchen basket for them incorporating soft silicone or wooden tools like measuring cups, wooden spoons, basting brushes, spatulas and more into their own basket that they can reach for and investigate—and even take a little taste.

3. Mess-free art

Encourage baby’s burgeoning art skills by placing a piece of white paper inside a reclosable plastic bag and adding a few squirts of finger paint inside. With the bag closed, demonstrate how to use your fingers to move the paint around inside the bag and blend it together to cover the paper.

Related: Montessori for babies: 4 simple ways to get started

Developmental activities for 8-month-olds

1. Mini architect

Your little one’s grasping skills are getting more refined, and they may now be able to help you build a tower—and then promptly knock it down. Show them how to stack blocks on top of each other to balance, and see how high they can go.

2. Show and tell

Pointing out interesting things for baby to see helps them understand that they can communicate this way with you, too. Whether you’re reading a book together, taking a walk or shopping for groceries, make a point to point out what you’re noticing for your curious kid, then tell them all about it.

3. Step by step

Though not ready to walk just yet, baby is ready to learn about balance and spatial awareness, which help support their early walking skills. Practice stepping movements to exercise those leg muscles. Support your barefoot babe under the arms during practice steps, bounce your standing sweetie on the lap, or provide assistance as baby cruises along sturdy furniture. No need for shoes at this stage—being barefoot helps foot muscles develop. Supervise use of a safe push toy (spy our pick below) to promote independent mobility.

Related: When do babies start walking?

Things to do with an 8-month-old

Child development psychologist Dr. Holly Ruhl shares fun week-by-week activity ideas for month eight.

Week 1: Take me out to the ballgame

Help baby hone their motor and social skills by rolling a ball back and forth, and to go next-level, show your cutie how the pros play at a real ball game! Your tot will love the songs, mascots, fireworks and halftime events. Keep baby happy with snacks, sunscreen and a tour of the stadium. Even free little league games offer baby a chance to behold an intriguing interplay between other children.

Week 2: Crawl along

Crawling or scooting strengthens the muscles babies need to start working on walking—and little ones love the puzzle of an obstacle course. Set one up with pillows and cushions to create a mini maze—then have them follow you through it for a cute take on ‘Follow the Leader’.

Related: 8-month-old feeding schedule and expert advice

Week 3: Go independent

Your little one can and should work on playing independently at this stage, too—you don’t need to be cruise director for your tiny tot. Baby just loves to be near you, so try to involve them in your day when possible, but know it’s also completely OK to do something just for you while they play safely nearby.

Week 4: Copy cat

Baby can imitate your actions even after a 24-hour delay. Exercise baby’s developing memory by modeling desirable behaviors for your babe to imitate. Use a spoon, brush your teeth or hair, share toys or care for stuffed animals, and then watch as your little one adorably tries to do the same.

Our favorite products for 8-month-olds

VTech Sit-to-Stand Learning Walker



Sit-to-Stand Learning Walker

As your little one begins to get their footing, push walker-style toys like this one are a great option. The wide base and handle make it easy for them to practice standing while a fun selection of buttons, spinners, lights and sounds provide endless entertainment. And if they’d rather play while sitting down, the entire front can detach to lay flat on the floor.

ECR4Kids SoftZone Climb and Crawl Activity Playset



SoftZone Climb and Crawl Activity Playset

A safe place to crawl and explore while also providing a cushiony place to crash, this foam climbing set is sure to get a ton of use. Each of the five pieces can be used together or separately to create a play space that’s fun from eight months all the way through the toddler years.

VTech Wiggle and Crawl Ball



Wiggle and Crawl Ball

There’s so much fun to be had with this interactive ball which wiggles and wobbles on its own. It’s not only a great way to encourage crawling, it also helps them learn colors, animal names and numbers. Additional features like a spinning turtle, sliding bird and twisting bunny give them opportunities to practice their fine motor skills.

Look ahead: Activities for a 9-month-old: Fostering baby’s development

A version of this story was originally published on Nov. 24, 2015. It has been updated.