Image layout varies by viewing resolution

Site URL: http://www.joyschreier.com/

I just went live today with my first site, and would greatly appreciate some advice on image sizing and layout.  On the bottom of my page, I have three images.  

I have the images set to 1:1.  When I view them on my desktop, all three images have the same height but the spacing is slightly inconsistent with a smaller gap between the first and second images than the gap between the second and third.  When I view it on my laptop, the third image is taller than the other two but the spacing is consistent.

I keep playing with various settings to get the height consistent between all three with good spacing, but have had no luck.

Thank you in advance for any help or thoughts you can offer.

Joy

I've tried to add in larger pictures, since the one having issues is the lowest resolution but that didn't seem to work.  Any suggestions are appreciated.