Your Son is a reason for him to have been proud, because he left this world knowing he had helped to raise a daughter, capable of helping to raise a decent, honest human being of their own, so he would have known he didn't fail.
You're a good Mother, because of his fatherly input and his grandson is validation of such input, when you were younger.
Remember him for the good times and never forget in some small way(s), he is a part of you, parhaps in certain things you say or do or think.
It's perfectly human to feel down about this, but there's no reason to be sad if you don't want there to be, because you had a lot of time in your life with him and there were obviously good times, because of how his passing makes you feel and the things he taught you, imparted on you, or did, that have influenced how you think, speak or act.
He was clearly a good man, because you ARE such a person yourself and a really, really good Mother.
So, WELL DONE on getting to this stage in your life and being like you are. It's fantastic and you are one of the most lovely, charming and quite emotionally beautiful people, anyone could wish to come across and you are a credit to your Father and his memory Lynne, you really are

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He did NOT live or die in vain, for he lived with a sense of purpose and he lived with the rewards of his purpose and he died leaving a legacy. A daughter who has and will continue to go on positvely influencing and touching many people. So his passing was a rich mans passing and his life a pretty fulfilling one too.
You do not need to honour his memory necessarily on Fathers day, because you do that every day, by simply being you

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I'm sending you a
BIG HUG and letting you know, I'm proud of you for all that you are and all that it means and represents.
You are a special Lady Lynne. THANK YOU for all your time, support of others and contributions. You are really, really appreciated

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