Milestones Big and Small

Why is it that every big milestone seems to take forever to arrive, and then once it does happen you wish you could go back?

Zachary is now crawling and pulling up on everything. He also has learned to climb up the stairs, and to throw temper tantrums. Where has my sweet innocent baby gone? He seems to have been replaced by a small cranky almost-toddler. He has also gotten 4 teeth in the last month, and now he bites me all the time. Luckily we gave up on breastfeeding at 4 months, or I would be hating this phase much much more! Still, it is surprising when your sweet baby crawls up to you, gazes at you adoringly and then chomps down on your big toe. Yikes!