An adolescent female with ventilator-dependent spinal muscular atrophy type 1 (SMA-1) and megalencephaly-capillary malformation-polymicrogyria (MCAP) syndrome had been struggling with recurrent small to large volume hemoptysis for years secondary to complex arteriovenous malformations (AVMs) in her lungs. Despite numerous embolizations, she continued to experience hemoptysis from new AVMs. She was then started on sirolimus (rapamycin) and remains hemoptysis-free for over 12 months. To our knowledge, there are no known cases of SMA-1 with MCAP syndrome and related complex vascular malformations successfully treated with sirolimus.