I think the answer is more obvious than you think.
Ironically, there is a certain degree of an all-consuming selfishness in Christian theology. We are to forsake all things to obtain that one Object that benefits us. This includes loved ones. In fact, if our regard for them is not HATRED relative to the Kingdom of God, then there is a problem.
May be obvious to some, but I can't imagine HATRED in Heaven, even "relative" hatred, in that all-encompassing love.
Death is uniquely a “self” event. Anyone with a lick of sense, on the event of dying forgets Earthly matters when they pass. Just as those left behind, forget about their relatives who have died over time. It is the nature of things.
To the contrary of all-consuming selfishness, while there is valid appeal to avoid suffering and obtain bliss, yet to be a true believer requires consent of sacrifice of self and all else in choosing to follow the Lord, and which includes unselfish dedication to the welfare of others. And perfect love is one of motivation to see God honored and others be one with him, even if it would mean your own damnation, though that result would be a contradiction of faith.
"Hate" of family pertains to loyalty to them over God, as in obeying the gospel and being baptized, etc. Using comparative terms, as as dedication to one equating aversion to a competing object, a true convert must also "hate" and his own life:
If any man come to me, and hate not his father, and mother, and wife, and children, and brethren, and sisters, yea, and his own life also, he cannot be my disciple. (Luke 14:26)
Watch https://tubitv.com/movies/507867/the-pilgrim-s-progress for an illustration as concerns family (begin at 6 min mark if pressed for time illustration is around 8:30) .