The 28-year-old pop star lost their dad to cancer in June 2013, and Demi admits it's always a tough day to navigate.
The 'Cool for the Summer' hitmaker - who had a strained relationship with their dad - wrote on Instagram Story: "Trying not to wake up sad.. Trying to stay positive. Today is always so difficult. This is for anyone else who's lost a father, can't be with their dad, didn't know their dad, or anyone who has a tough relationship with their dad. I spent many years on this holiday wondering whether or not I should call him.. take it from me, if you can, make the call.
"Some days I regret not calling but other days I'm proud of myself for holding my boundary because I was doing what was best for me and my mental health. It's complicated, and I wish it were different but this made me into the person I am today. Anyway my heart goes out to the people still holding their boundaries as well. (sic)"
Meanwhile, Demi has admitted that their messages have "got lost in translation" over recent years.
The chart-topping singer - who recently came out as non-binary via Twitter thread - believes it's easy for messages to become confused over text.
Demi - who launched a new podcast earlier this year - said: "I'm very outspoken about a lot of the things that I believe in and I feel like sometimes my message gets lost in translation over text ... I find when I'm able to show the world my heart, it shows that my intention is coming from a good place.
"And so, I wanted to have conversations that showed people that I really am invested in making this world a better place."
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