My prayers for your special child (and your whole family, Thekla, my friend).
Yes, when you're confronted with such tragic and serious news, it's quite overwhelming, and the praying comes after the shock and disorientation has dissipated. I hadn't prayed to the Saints or the Theotokos at the time because I never had and didn't think to do so (also I didn't know how). I was a semi "convert" even though I was also a "cradle," but wasn't taught all this growing up. So, eventually a couple years ago when I got dire news on my son's MRI at the time, and husband was still in S. Korea doing a military unaccompanied tour, it was just me here, and I prayed, and the teachers at the school my boys went to prayed, my family prayed, there are monks praying for him like I mentioned, and all friends and family. Then I turned to the Theotokos and St. Nectarios and St. John the Wonderworker and I asked them to please pray to our God that my son's tumor not grow...that he be healed if it's in His Will. Within an hour, the heavy, grievous burden on my shoulders was lifted off, and my worries left. This had never happened before. So I totally believe in asking those righteous in heaven to pray. The next doc's appointment, the tumor hadn't grown but shrunk a bit, and the cyst it had produced had shrunk down as well, which it had never done before. Glory to God! Thank the Saints for their prayers!!