8.5 Months

To properly appreciate this story, you have to understand the layout of our house - it's split-level, so each of the levels are separated by 5-8 steps. The basement is the only carpeted area, so that's where we spend a lot of playtime with Fuzzy - there's basically no furniture, just all of his toys scattered around. The nearest bathroom is up the first half-flight of carpeted stairs.

Anyway, Maya was playing with Fuzzy in the basement while The Pit and I were at work, and, being human, she felt the call of nature.  She stuck Fuzz into a giant pile of toys in the corner, and ran upstairs to the bathroom.  Suddenly, she heard a noise at the bathroom door, and nearly had a heart attack, thinking that there was an intruder trying to break in.  She opened the door, only to find Fuzzy sitting there smiling at her, and curiously peering into the bathroom to find out why he was excluded.

Granted, it's only 5 steps, but we still found his feat pretty amazing, considering he's only shown cursory interest in the stairs in the past.  Before he could crawl, if left alone in the basement Fuzzy would just wail until somebody returned to play with him.  Once he got the crawling thing down, he would first move over to the base of the stairs, and then proceed to the customary wailing.  And now, suddenly, in one afternoon, I guess he just up and decided that the mountain could come to Mohammed after all.