I sleep when I'm tired. I start to get tired at 3 AM.
"Circadian rhythm abnormalities are also extremely common in ADHD, especially in the form of delayed sleep (sleep initiation insomnia). It has been genetically linked by findings of polymorphism in genes in common between those apparently involved in ADHD and those involved in the circadian rhythm[4][5] and a high proportion of DSPD among those with ADHD,[6][7] however no specific or further cause-effect relationship has been proven." (Wikipedia)
DSPD refers to Delayed Sleep Phase Disorder, which is characterized by a much later than normal timing of sleep onset and offset and a period of peak alertness in the middle of the night.
I inherited that shit from my dad. My mom's a lark.