Lohan has previously described her father as a "lunatic", a "loser" and a "deadbeat dad" following his claims that she is addicted to prescription drugs.
However, Radar Online says that Lohan decided to contact her dad after he suffered a heart attack this week.
Michael said: "I got a text message from Lindsay which read, 'OMG. Hope you are okay', and my other kids have all been in contact with me, too. My girlfriend Kate Major slept here with me overnight and my spirits have been lifted by the support from both my family and friends."
He continued: "I've been through a lot in my life - been to jail, various court cases, even drove my Ferrari over a cliff once - so it's going to take a lot more than this to finish me off.
"Hopefully the procedure will go well today and I expect [my ex-wife] Dina and the kids to come and visit me later today."
This is the second time in a month Michael has been treated in hospital for his heart.