No. Like I just said five seconds ago, this idea of "locking in" insurability or rates is a scare tactic. Unless your kid is an Cartman-grade fatass, the odds are that they're not going to get a pre-existing condition that disqualifies them from coverage. These are vanishingly rare. Insurance salesmen try to scare you with "oh but what if your kid gets heart disease at age twenty"? This
shits me to tears. Your kid is not going to get heart disease at age twenty, or thirty, or forty, or probably even fifty, and it's not worth paying sixty years' worth of premiums so that your kid can have term life coverage when he doesn't even need it.
Also, think about this - when you die you'll be saddling your kid with an insurance policy they might not want. That's kind of a dick move - you're leaving them with the opposite of a phat inheritance. Don't be a dick. Don't do that to your kid.
You, and your kid, should only buy insurance when you need it. For term life, that's "when you have dependents".