Dilemma

I just had a 1:1 meeting with my boss (small boss)....
I am upset....
I am really in a dilemma....
I don't know what to do....
I want to go home to visit uncle....I want to be there for him to support him all the way through...
I want to be with him before the operation, when he is admitted, during the operation (standing outside the theatre) and after the operation....
BUT...I have 2 major presentations next week; one on Monday to my boss and also my entire team, then on Tuesday at 7am in the morning, I need to present a training to my US boss and other teammates....then on Wednesday, I have to attend a training....

Tell me, what should I do??
If you think these are merely excuses and can be delayed, I don't think so...because, I have already pushed off a couple of these presentations previously due to trip, late notice, etc...
And I cannot delay anymore....I am really stuck here....
Can someone help me out?
I am suffocating...
I am so unhappy....but I will continue to pray for my dear uncle....
God bless him....I will try to be back asap to see you:)