Sophia is still in the 50th% for weight (13 lbs at 4 months) but she grew a lot in length and is now in the 90th% for length (25.5 in ?) and her head is in the 95th % (17 in. I think).
She started laughing out loud around the time she turned 4 months and she now spends time daily playing on her tummy on the floor.
She finally started enjoying her baths.