If you are talking about birthdays, etc..., I would say yes. I don't, however, consider them holy days. I still am not sure how honoring a sinner saved by God's grace is considered "Holy"?
"Holy"
Definition -- not a "state", but "set apart unto the Lord".
Learned that as a Protestant, by the way.
It is simply a day set aside unto the Lord in which we celebrate the Lord's work and grace in that person's life. It is HE, after all, Who makes the sanctity of that sinner possible. To teach anything other than that is the heresy of Pelegianism. (self-effort).
I know that from your vantage point it doesn't seem this way, but the Catholic teaching really is that it is all of God and all of grace. That we co-operate with His grace does not make it "works". "Works" is trying to make your own covenant with God OUTSIDE OF AND IN DEFIANCE OF THE WORK OF CHRIST UPON THE CROSS FOR SINNERS.
Big difference.
Best way I can explain it again is the Hindu who goes yearly to the filthy Ganges River and "baptizes" himself for the remission of his sins.
WORKS.
Pure and simple. Goes in a dry sinner, comes out a wet sinner.
Why?
Because he is doing it OUTSIDE OF THE WORK OF CHRIST. No reference to the Cross at all in that baptism. It is man...acting on his own to try to please God when God has given His Son...His very best.
The Transfiguration of Christ (the Last Adam) and the Assumption/Dormition of the Blessed Virgin (the New Eve) should be such a great encouragement to us. In both of them, we see humanity elevated by the work of God, One from within, and one from without. Their glorification is our destiny as believers.
REJOICE!!