The thing is: man ejacuates early because of few things.
(1) He is too much excited to have sex. In this condition man ejacuate early. Here excited means he is already having sex in his mind. That is what is happening with your neighbour boy. In this case make him calm down and start sex slowly.
(2) when man enter his dick in pussy then due to heat and sensation he ejacuate early.in this case one should use thick dotted condom..it will decrease his direct contact with pussy and he will fuck for more time.
(3) sometimes it's medical issue that can be solved only by DR.
Few tricks can be used to make this fucking session longer.
(1) this is the best remedy..always give a handjob or blowjob and make him cum first before he touches you..it means when u or ur neighbour are going to have sex don't let him touch u .first u directly take his cock in ur hand or mouth and make him ejacuate.when he ejacuate then the real foreplay and sex begins..normally after this man ejacuate very late..
(2) u tell ur hubby and neighbour to master bet just before having sex.then he will stay longer.
(3) tell ur hubby and neighbour to be not in hurry..mostly man fuck for longer session because normally after 7 to 10 minute man ejacuate but when they feel like ejacuation they pull their dick out of pussy or ass.then they wait for few minute normally 1 to 3 minute and during that time man start fore playing with the girl..during that 1 to 3 minute they lick pussy,eat them,fingered them..play with tits,tongue,arm pit,lick ass hole etc.so this way they stretched fucking session to 1/2 hr.many man use dildo for fucking when they pull their dick.this way ur pussy or ass will be continuously filled with dick.
(3) the last,they use viagra for longer erection.this way they also don't ejacuate.but using viagra is not healthy if it is regularly taken..for twice or thrice in a month it can be used.normally after taking viagra man will fuck for minimum 1 hr and still he will not ejacuate.
So these are few small tricks that can increase ur fucking session.if all these didn't work then I will suggest u to make ur self satisfied with fingering,can use dildo,vibrater or u have to look for another man who fuck u without disclosing this secret.