Jana Duggar isn't one for regular Instagram posts but the 31-year-old took to the social media site on Saturday to share a video of a fun day out on the lake.The eldest Duggar daughter hit Beaver Lake in Arkansas' Ozark mountains and shared footage of herself riding a bright yellow jet ski."Feels like summer!!" she captioned the post, adding the hashtags "#beaverlakearkansas" and "#lakehairdontcare."MORE: Everything you need to know about the Duggar family weddings WATCH: Jana Duggar shares rare