She is one proud mama after watching her 18-year-old son Jayden showcase his smooth piano skills at her house Monday night -- in their second reunion since the holidays. Britney Spears showed off her youngest son's piano playing in an Insta clip she shared and was clearly blown away as she described the moment as "so sick." She further gushed in the video's caption, writing ... "WOW WOW WOW !!!"
The enthused singer exclaimed ... "My son just played, oh my God! I felt it in my bones, and my heart, and my lungs, and my ass, and my throat and I'm scared!"
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