Haha thanks, well, I knew the meaning of it but the origin skips me by without cheating with Google - this result badly explains but I guess it means the 'T' is shorthand for 'tittle', as in, the dots over i's and such. Makes sense!

This year, the bride and I celebrate 45 years

That's crazy. I don't think I can even live long enough to get that far anymore... I'd be 82!