"Happy plank day" is every day. It doesnt really mean anything.
Timmy: Happy plank day!
Happy treesh day is the definition of treesh it’s just a special day for the treesh people.
Lonely people hooking up on Tinder so they won't be alone on Valentine's Day.
Happy Valentinder's Day: Candice is so lonely that she's on Tinder just so she won't be alone on Valentine's Day...