You are absolutely right to say that all things pass. The bad as well as the good. It's a blessing that we humans forget, forgetting is a blessing in a sense. Otherwise we cannot get up from the pain and unfortunate events.

And i feel Mother's Day is a misnomer.
Every day should be Mother's Day.
There’s nothing we can ever do that can express enough of our gratitude and thankfulness to them.
Love her, honor her, and show your gratitude and appreciation to her.
Please have a wonderful Mother's Day celebration.