A family source tells PEOPLE that the Grammy winner's diagnosis has "brought clarity to a series of unexplained issues" as Biel has been "incredibly supportive"

Justin Timberlake has announced on Instagram Thursday that he was diagnosed with Lyme disease. The former NSYNC singer shared the news in a post commemorating his two-year Forget Tomorrow tour, which wrapped in Turkey on Wednesday.

When Justin Timberlake revealed that he’s been battling Lyme disease on Instagram, it lit up the internet. Some people sent well-wishes, others asked questions about the illness, and a few—of course—propagated bucket loads of misinformation.