Sleep regression

So my daughter is almost 5 months old (17th) and just now going through the sleep regression. She sleeps in my arms at night as she hates sleeping in her crib ( I think she will be a tummy sleeper like my son) but instead of sleeping from 10 pm - 6:30 am she wakes at 4 am for 8 ounces and then wakes again at 6 for 6 ounces. Come 8 am she has her oatmeal with fruit and then sleeps for 45 min and is just so fussy lately! Any suggestions? My son is 8 years old so I completely forgot this stage. Thank you!