There is no minimum age for Maha Samadhi and there is no rule for young ones that could prevent Maha Samadhi at any young age! The rules are the very same for youngest and for oldest = to love all and to practice complete kriya yoga with God and Love in mind and heart.
When youngest ones leave for God, then parents and sisters as well as many loved ones or friends usually review their own values in life as well as purpose of life on earth and may change heart and mind and entire lifestyle. Hence any death or Maha Samadhi of loved ones at youngest age may often benefit many others much better than getting old and older. A sudden death as well as conscious Maha Samadhi often is a most intense and most efficient “wake up call” for lost ones to reorient their life toward the spiritual goal of all human souls – to return home to God.
Death always has the greatest impact on loved ones lost on a non-spiritual path, often far more powerful than thousands of spiritual talks and lessons of love.
All those among you who do for an extended period of time unlimited kriya yoga besides daily work, make sure you have pre-paid and prearranged your funeral as that might be the last part of a life that needs to be clarified and arranged by a human preparing for Maha Samadhi.
Whatever left behind when you fully surrender to God, then will become part of the needed spiritual lessons of all your lost ones among your friends and family members.
Do whatever you do but always do it to the greatest possible perfection. There is little to no room for errors or superficiality on your path of love home to God. God is Love and love is the key to God. Love in all your actions, work, business and other activities.
As the ultimate spiritual qualification for Maha Samadhi is to achieve the one major goal in life – to love all, to forgive all and to reconcile with all. Learning to love is the only purpose of life on earth. Any additional lessons can be learned at home in God’s world of love in a far more loving and pleasant environment as part of our eternal life in God.