Great-grandfather Wilson (L), 77, kisses his great-grandson Juan Pedro as his mother Daniele Santos, 29, holds him on a street in front of their house in Recife, Brazil, Feb. 9, 2016. REUTERS/Nacho Doce

Sunday is National Grandparents Day, a secular holiday celebrated in the United States since 1978. It is meant to be a day set aside aging relatives and tell them how much you care about them.

Here are 15 quotes from Saying Images, Legacy and Quotezine to remember and honor the elders.

1. “A grandma is warm hugs and sweet memories. She remembers all of your accomplishments and forgets all of your mistakes.” – Barbara Cage

2. "Because grandparents are usually free to love and guide and befriend the young without having to take daily responsibility for them, they can often reach out past pride and fear of failure and close the space between generations." - Jimmy Carter

3. “Maybe that is the greatest of wonders: that we can be shaped so much by those we've known closely, and equally by those we've never known at all and that we too can change the world long after we've left it.” - Jacob M. Appel

4. “We should all have one person who knows how to bless us despite the evidence, Grandmother was that person to me.” – Phyllis Theroux

5. "The simplest toy, one which even the youngest child can operate, is called a grandparent." - Sam Levenson

6. “To a small child, the perfect granddad is unafraid of big dogs and fierce storms but absolutely terrified of the word “boo.” – Robert Brault

7. “What a bargain grandchildren are! I give them my loose change, and they give me a million dollars’ worth of pleasure.” – Gene Perret

8. “A mother becomes a true grandmother the day she stops noticing the terrible things her children do because she is so enchanted with the wonderful things her grandchildren do.” – Lois Wyse

9. “Nobody can do for little children what grandparents do. Grandparents sort of sprinkle stardust over the lives of little children.” – Alex Haley

10. “Uncles and aunts, and cousins, are all very well, and fathers and mothers are not to be despised; but a grandmother, at holiday time, is worth them all.” – Fanny Fern

11. "What children need most are the essentials that grandparents provide in abundance. They give unconditional love, kindness, patience, humor, comfort, lessons in life. And, most importantly, cookies." – Rudolph Giuliani

12. “ Being grandparents sufficiently removes us from the responsibilities so that we can be friends.” – Allan Frome

13. “ The history of our grandparents is remembered not with rose petals but in the laughter and tears of their children and their children’s children. It is into us that the lives of grandparents have gone. It is in us that their history becomes a future.” – Charles and Ann Morse

14. “ What is it about grandparents that is so lovely? I’d like to say that grandparents are God’s gifts to children. And if they can but see, hear and feel what these people have to give, they can mature at a fast rate.” – Bill Cosby

15. “ You do not really understand something unless you can explain it to your grandmother.” – Proverb