I had up to 20 years between episodes. First one at 10 years then, bad one at 15, mild one at 35, and at 45 was dxd SPMS. Had a full & happy life so its great to have long gaps. Good luck.
Have had relapsing/remitting MS since 10 yrs old. Secondary/progressive since 1995. Baclofen pump since 2008.
Row, row, row your boat gently down the stream
Merrily , merrily, merrily, life is but a dream