S.H.
My daughter is 17 months old and has all 4 of her first molars, all 4 central incisors, and is just recently getting at least 3 of her 4 lateral incisors. There is a chart for tooth eruption & shedding at http://oralhealth.uchc.edu/Eruption%20Chart.pdf. The chart shows that the first molars can come in between 13-19 months, so this is normal! It also says that the first teeth are shed (central incisors) between 6 and 7 years. I'm sure your daughter will lose her first tooth in a year or so. The chart says the upper lateral incisors should come in around 9-13 months. But I just noticed last night that my 17 month old's just broke through! They will come when they are ready, and I'm sure they will fall out when they are ready! :)
Does your 7 year old see a dentist regularly? You could ask at her next visit, or just call the dentist's office and ask if there is a point when baby teeth need to come out before causing damage.