My daughter is 4 months and she has a H on her nose. I asked about if there could be internal H's. I see a specialist and he told me because she only had one not to worry, it's more common in children that have more than one.
But like I always tell people I would rather be safe than sorry.
A mother always knows when something is wrong and if you feel that you need a ultrasound or MRI do it if your able to. What could it hurt. But just to let you know when they talked about doing an MRI on my daughter they told us she would have to be put to sleep, for an ultrasound she don't.