BTW - I'm a Libra with Cancer Moon too, in case you didn't know that already.I'd say of the four, you may have more ego struggles with the "1st & 4th Son". Perhaps I'm way off, so don't take me too literally because it goes without saying you know your children and your circumstances. If you have some compatible Leo or 5th House influences, or Sun aspects, or even some strong Fire or Air influences in your chart (other than being Libra), OR, if the two have any compatible Scorpio, 8th House, or Pluto aspects, OR, Water or Earth influences, it may be easier.
Not to say Leo & Scorpio don't get along because each chart is unique. But they are both Fixed Signs who don't take criticism lightly, and who would rather forge their own way.
I'm sure you'll get some more responses from others with more perspectives.
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... it's better to light a candle than curse the darkness