Baby budgies

Question
I have three baby budgies: the oldest one is 39 days old, the middle one is 37 days old, and the youngest one is 33 days old.

Up until now, the female parent budgie has been raising these chicks alone, as the male died after the second chick hatched :(. However, the female has recently become very aggressive towards the chicks. She would chase them around the cage and violently peck at them.

I separated the female from the chicks this morning. The babies are pecking at the pellets and seeds I put on the floor of the cage, but I'm not sure if they're eating them. Without the female to feed them, I  hand-fed the chicks with some hand-feeding formula today, but they didn't seem too eager to receive it. I used a syringe, warmed the formula to around 38 degrees Celsius and rubbed the chick's beak to try to get a feeding response. I think they ate a little, but not a lot. I'm going to try and hand-feed again tonight (i.e. twice a day).

My question is, am I doing everything I should in this situation? Am I doing it correctly? I'm just concerned if the chicks are getting enough food. The two oldest chicks are moving around, perching and preening as usual, but the youngest one seems to sit in the nest box alone.

Your help would be much-appreciated! Thank you!

Answer
http://www.lafeber.com/products/feeding_instructions.asp     this offers all teh insight you will need, you do seem to be doing everything right thou....I didnt use a temp gage to test my formula i jus tested it on my wrist if it burns its too hot if it feels cold its too cold you should barely be able to feel it on your wrist as it should be body temprature.