Britney's Boo Boos Get Their Own Padded Room

9/14/2008 10:31 AM PDT
They grow up so fast -- Britney and Jamie Lynn, that is.

Jamie Lynn and baby Maddie showed up for Britney's joint birthday party for Jayden James (2) and Sean Preston (3) yesterday -- where Brit and her "weave you see from space" watched the kiddies play in an inflatable jumper.

Brings back memories.