I'm so sorry KD. My Robyn did the same thing around that age, and I thought the same thing, seems like colic but arent' they too old??
Now the weather is nicer, can you go for a long stroll with Landon in the sling What if you got the other kids bathed and in their PJ's before you go. We used to do this with Raynbow when she was about 5 or 6, she loved to be out in her 'jamies' and to be honest probably nobody could notice they were pj's. Put their boots, or shoes and a jacket over them, put Landon in the sling, and out you go. Heck it's a good idea even if your baby isn't cranky.
good luck
anni