Holding onto the BTC until they are able to handle it themselves is the best approach. Who knows how much BTC has been lost due to irresponsible gift-giving.
But, depending on the person, it might be appropriate to not tell them that you bought BTC for them. Some people will be offended by "till you're ready". Moreover, most people don't understand the value of Bitcoin, so some might be offended that you gave them what is from their perspective a non-gift.