I don't agree with this saying at all.
Teach your children from birth to respect all forms of life. Respect is not earned, it is learnt. And out of that respect, love will grow. If it doesn't, it won't last.
You can't love someone that you don't respect, or whom you have lost your respect for. Love is earned.
It's not love that cultivates respect. Respect cultivates love. Easy as that.
Take care!