A puppy gains about 10-15% of its birth weight every day, which explains why they look bigger every time we see them! Having pets and watching them grow up is one of the best feelings in the world and to spread the happy vibes, pet owners are sharing the transformation photos of their babies.

Bright Side has selected 15 of the most impressive pet glow-ups for your daily dose of serotonin.

1. “From 2.5 months to nearly 2 years”

2. “Casper at 3 and 13 weeks old.”

3. “8-week-old puppy to 9-month-old derp”

4. A majestic glow up

5. “Hjalmar on the day I got him, and exactly one year later!”

6. “Bean was a microkitten. Here she is at 8 weeks vs 5 years.”

7. “2 months to 12 months. We love our big floofy Samoyed boy.”

8. “puppy snoot -> doggo snoot”

9. 8 weeks vs 6 months

10. “Marvin 1 month to 1 year”

11. “Thor, then and now”

12. “From day 1 to 8 weeks to 1 year old”

13. “My old girl turned 14 today.”

14. “From 3 months to 3 years”

15. When you’re huge but still a baby inside:

How much has your pet changed since you got them? Share their photos with us in the comments!