Carrie Underwood hit the high notes while singing "Happy Birthday" to her son Isaiah this week by sucking on a helium balloon before launching into the song.
Husband Mike Fisher Instagrammed a video Wednesday night that shows the 35-year-old country star inhaling helium from a yellow balloon while now-4-year-old Isaiah sits next to her in a chair and looks on.
The toddler was obviously delighted by his mom's high-pitched voice, asking to suck on the balloon himself once she was done.
The clip also shows Underwood holding second son Jacob, who was born in January.