Irving Berlin,the famous Jєωιѕн American songwriter did much to help secularize Christmas by changing the Birth of Christ into a sentimental song about snow:

White Christmas
Introduction
The sun is shining, the grass is green
The orange and palm trees sway
There's never been such a day
In Beverly Hills, L.A
But it's December the twenty-fourth
And I am longing to be up North

[Verse 1]

I'm dreaming of a white Christmas
Just like the ones I used to know
Where the treetops glisten and children listen
To hear sleigh bells in the snow

[Verse 2]
I'm dreaming of a white Christmas
With every Christmas card I write
May your days be merry and bright
And may all your Christmases be white

[Verse 3]
I'm dreaming of a white Christmas
Just like the ones I used to know
Where the treetops glisten and children listen
To hear sleigh bells in the snow
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As for Easter, he replaced the Resurrection of Christ with an Easter Parade:

Easter Parade
In your easter bonnet, with all the frills upon it,
You'll be the grandest lady in the easter parade.
I'll be all in clover and when they look you over,
I'll be the proudest fellow in the easter parade.

On the avenue, fifth avenue, the photographers will snap us,
And you'll find that you're in the rotogravure.
Oh, I could write a sonnet about your easter bonnet,
And of the girl I'm taking to the easter parade.