Foster/Pre-Adoptive Infant-Experiences?

Hi there, My wife and I had a foster/pre-adoptive placement of a 6 month old girl placed with us on 12/29/17. We took her after a hospitalization for the latest of injuries she sustained in her birth Home. First she presented with an unexplained broken arm then was hospitalized for a depressed skull fracture with no explanation by birth parents. A healing broken rib was found at the time of hospitalization as well. Luckily she recovered beautifully with no lasting effects. After an initial 72 hour hold, her 4 and 11 year old siblings were returned home as the didnt sustain injury with stipulation that birth dad stays away. This family was followed by DCF in 2015 first when another infant died in the home due to co-sleeping. Due to the severity of her physical state, she was placed in pre-adoptive placement with us. As you can imagine, we’re simply in love with her as is our 3 year old son and she is growing and doing beautifully. Our SW from DCF stated she’s not seen a case with this level of physical issues be returned to birth parents in her 17 years as an adoptive worker. However, we are gravely concerned that the 4 and 11 year old returning home is a curveball. We, of course, want to believe that no judge or human would dream to put this girl back in that Home given the pattern with infants over the past few years. I live in Massachusetts. Has anyone had similar stories or experiences with foster/pre-adoptive kids? Outcomes? Any insight into your experiences or thoughts would help. We know this is going to be a lengthy process. We just feel like hearing some real experiences could help with our focus and worries. Thank you!