Do NOT worry about the apparel!
When my dad died suddenly 24 years ago, I cannot remember any clothing item worn but I can remember the High School sports' teams who came and gave their respects
God Bless Your son for wanting to go 



I think the outfit you described would be perfectly acceptable. It isn't about the clothes you are wearing but the fact that he cared enough to show up and pay his respects.
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My mom's memorial service is this Saturday. For years, actually as long as I can remember she said that she did NOT want people to wear black to her funeral. She HATED black. My Dad made it known to all of us and at church that he hoped that people would wear bright colors. Mom's favorite color was pink. I have chosen to wear a brightly colored hawaiian shirt...with lots of pink in it and my pink and white Crocs Islander's,(Crocs were mom's all time favorite shoe.) and a khaki shirt.
I think it will make her smile....and I really don't care what anyone else thinks.
Linda
My mom's memorial service is this Saturday. For years, actually as long as I can remember she said that she did NOT want people to wear black to her funeral. She HATED black. My Dad made it known to all of us and at church that he hoped that people would wear bright colors. Mom's favorite color was pink. I have chosen to wear a brightly colored hawaiian shirt...with lots of pink in it and my pink and white Crocs Islander's,(Crocs were mom's all time favorite shoe.) and a khaki shirt.
I think it will make her smile....and I really don't care what anyone else thinks.
Linda
My mom's memorial service is this Saturday. For years, actually as long as I can remember she said that she did NOT want people to wear black to her funeral. She HATED black. My Dad made it known to all of us and at church that he hoped that people would wear bright colors. Mom's favorite color was pink. I have chosen to wear a brightly colored hawaiian shirt...with lots of pink in it and my pink and white Crocs Islander's,(Crocs were mom's all time favorite shoe.) and a khaki shirt.
I think it will make her smile....and I really don't care what anyone else thinks.
Linda
It's fine.
If someone is arrogant enough to think it's rude, well, they're welcome to buy your son a pair of "appropriate" shoes.
Thanks! I was not very close to her, but it still is really sad. She was just diagnosed with cirrhosis and liver cancer three weeks ago. She was not ever a drinker and they don't know what caused it. I'm very sad for my uncle and the kids, grandkids and great grand-kids. She was around 70 years old and seemed fine when I saw her in January.
I am so sorry for your loss...
Did she have a cold recently, by chance? 2 people in my life have died recently - both developed cirrhosis/liver cancer after having a cold/taking cold medication! The doctors of both said it is a lot more common than one would think - that cold medication really messes with the liver!