Girls, hello ? My baby is one month old today, we had a scheduled ultr…

Girls, hello ? My baby is one month old today, we had a scheduled ultrasound and found a cyst of vascular connective tissue in his head. I'm shocked, the neurologist said to observe, another ultrasound at 3 months. I can't find my place, anyone who has dealt with this, what was the treatment like? How did it go? Thanks.