While it is easier for a couple if both of them are Amritdhari, if a Sikh wants to take Amrit, they should take it. It is a recommendation, but not a limitation. Gurbani states that Amrit is for those who have the thirst within them. If your partner is not ready to take Amrit now, but they support you, you should take Amrit without any delay because the next breath is not guaranteed. 

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