MummyPig, 21 weeks is a little under 5 months as a month has roughly 4 1/2 weeks. So your ticker sounds pretty spot on with 4 months, 3 week & 6 days.

About the amount: I wouldn't worry too much about precise amounts. Take her lead. You will probably find that she'll have days where she wants to eat lots, and days where she's not all that interested.

Having said that, at her age, the majority of her nutritional needs should be met by breast milk or formula (util about 12 months). Are you breast or formula feeding? Offer her the breast or bottle before a solid meal to make sure she gets enough milk. Offer her some water with her food, but not too much so she doesn't fill up on it.

Solids are such an exciting thing. Have fun experimenting!

Sasa