Looking at your code, both images are formatted for WordPress to display them at the full size. My guess then, is that something happens on your ccomputer/device to resize the images.
For example, Dad in the orange/red shirt is 166×411 pixels. Was that a cell phone image?
Another example, your headshot is much larger, maybe another camera that takes larger images (277×251).
Are you using a photo editor of any kind between camera and uploading them?