Alex's little brother, Llŷr, passed away in July 2020, taking his own life after a battle with his mental health. Now, posting on Llŷrs birthday, Alex wrote, "Today would be your 20th birthday.
"You were 14 in this picture. I remember how proud you were of me graduating as doctor. You ran up to me after the ceremony with the biggest smile.
"I was so excited for you to follow in my footsteps, you would have been the most amazing doctor."
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Jack Fincham - then and now
Mr Colgate looks completely different in this old photo of him in the boxing ring. The self-proclaimed pen salesman has definitely found himself (and a self-tan mitt) since then and is now giving use all the feels with almost-girlfriend Dani Dyer.
He continued, "Although I would never admit it to you, in honesty you were the smarter of the two.
"We are ten years and four days apart, this was supposed to be the start of your 20s. You would have loved medical school and gone on to achieve so much.
"The very kindest of souls."
In the past year, Alex has worked to raise awareness for mental health and partnered with Bauer's Where's Your Head At? campaign in 2019 to promote active support for mental health in the workplace.
He has been vocal on his social media about being kind to one another through lockdown and beyond and in January, he even launched a bath bomb company to raise fund for Young Minds UK.
Now, remembering his brother, Alex - who is open on Instagram about grieving - told followers, "I think about you every single day my boy.
"It is impossibly hard at times, we miss you so much as a family. I have always been so proud of you. I hope you are proud of me. Love you my boy x.
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Recently, it was announced that Dr. Alex would be taking on a new role as a Mental Health Ambassador for Prime Minister Boris Johnson.
Announcing the news on his Instagram, the former Love Islander wrote, "WE DID IT!! You called and the PM answered!!
"I have been appointed as the Ambassador for Mental Health. It hasn’t sunk in yet and I’m not sure it ever will. I am truly humbled."
The 30 year old explained that he will be help to push the importance of mental health - in line with the government - in schools, universities, "the NHS and the wider public."