Poem for my son's 21st (Written in haste)

There was a bloke called Luke M Batt
Whose father was an utter twat;
Who woke one day and loudly cursed
“Oh, Damn! I’ve missed Luke’s twenty-first!
Well not exactly missed the day
But bought NO CARD with which to say
‘Hey, Luke, I hope you’ll have a blast
Before this happy day has passed”.
And so his dad dashed off a rhyme
Knowing he still had some time
Upon his words to ruminate-
As Luke would often get up late.
Hence these syllables inept,
Written as his son still slept.
Twat or not, his dad was clear,
“Have another wicked year!
And when you’ve kids of twenty-one
Do not do what I have done!
Buy a card, or to be sure,
Write your verse the night BEFORE!”